Although many people thought she just didn’t want to gain the baby weight, it turns out Jillian suffers from endometriosis.

Trainer Jillian Michaels, 37, who is currently in the process of adopting a child and becoming a first-time mom, confessed over the weekend that she struggles with infertility. Last year, Jillian said she wouldn’t want to carry a baby herself because she couldn’t “handle doing that to my body.” And although that comment stirred up a lot of controversy, Jillian explains that it was not about putting on weight, but was addressing the fact that she has endometriosis. Sad news.

“I most likely couldn’t get pregnant,” she tells The New York Times. “I’ve had the X-rays, my tubes are closed, the uterine lining is too thick, blah, blah, blah.”

“I was ashamed about it because I thought I’m supposed to be the healthiest woman in the world, and what does this say about me if I can’t have kids of my own,” she says. “It was insecurity, which I have to work on.”

A friend of the Biggest Loser star says it took a lot of strength for Jillian to confess her fertility issue. “Jillian would much rather have kept her private life private,” a friend tells PopEater‘s Rob Shuter. “She thought the nasty comments would stop, but once it became clear that they wouldn’t, she felt the need to address it head-on.”

There are so many women out there who battle infertility, including celebrities like Nicole Kidman and Khloe Kardashian, and the source says that if Jillian “can make just one woman struggling to conceive right now feel better about herself then it was all worth it.”

We hope Jillian gets the family she dreams of, as well as other women struggling with similar fertility problems.